Monday marked the beginning of the end for General Chemical Corp. as the company started scouring and shutting down its Leland Street hazardous waste handling facility.

Company president Michael Persico was on site as the firm officially began the laborious decommissioning process, expected to take several weeks.

The state Department of Environmental Protection is overseeing the cleanup and monitoring air quality. Agency spokesman Ed Coletta said he expects to see results of the first day's work today.

As was the case during a pilot test in late June, General Chemical prohibited Framingham Board of Health representatives from stepping on site, although it allowed fire officials in.

"They would not grant us access to the property, which was expected," Health Director Ethan Mascoop said.

Tensions are high between the town and the firm, which told the DEP on March 1 it would close. The Board of Health was in the process of considering whether to revoke or rescind General Chemical's site assignment in light of public health concerns and waste handling violations.

The Board of Health on July 9 voted to issue a new site assignment to regulate the facility as - and after - it closes.

Behind closed doors, selectmen have recently discussed a potential legal fight with the company, which is under pressure to clean the buildings and dismantle the waste storage tanks at 133 Leland St., and then target a plume of contaminated groundwater encroaching on the neighborhood.

Closure activities are scheduled to continue daily, except on Sundays, through Aug. 15. For more details, visit www.mass.gov/dep/about/region/gcc.htm.

(Danielle Ameden can be reached at 508-626-4416 or dameden@wickedlocal.com. Follow her on Twitter @DanielleAmeden.)